<html>
<canvas id="a_canvas" width="1600" height="600"></canvas>
<script>
     
               (function (){
 
        window.addEventListener("load", function(){
 
          var data_x = [0,100,200,300,400,500,600,700];
          var data_y = [0,100,200,300,400,500,600,700];
          var data_list = [[100,200,300,400,500,600],[200,300,500,400,700,100]];
		  strokeStyle_list = ["#8BA9FF","#555555","#AAAAAA","#000000"];
 
          // 获取上下文
          var a_canvas = document.getElementById('a_canvas');
          var context = a_canvas.getContext("2d");
 
 
          // 绘制背景
          var gradient = context.createLinearGradient(0,0,0,300);
 
 
          // gradient.addColorStop(0,"#e0e0e0");
          //gradient.addColorStop(1,"#ffffff");
 
          context.fillStyle = gradient;
          context.fillRect(0,0,a_canvas.width,a_canvas.height);
 
          
          // 描绘边框
          var grid_cols = data_x.length + 1; // 竖方块的个数
          var grid_rows = data_y.length + 1; // 横线方块的个数
          var cell_height = a_canvas.height / grid_rows;
          var cell_width = a_canvas.width / grid_cols;
          context.lineWidth = 1;
          context.strokeStyle = "#a0a0a0";
 
          // 结束边框描绘
          context.beginPath();
          // 准备画横线
		  for (var col = 0; col <= grid_cols; col++) {
            var x = col * cell_width;
            context.moveTo(x,0);
            context.lineTo(x,a_canvas.height);
          }
          // 准备画竖线
          for(var row = 0; row <= grid_rows; row++){
            var y = row * cell_height;
            context.moveTo(0,y);
            context.lineTo(a_canvas.width, y);
          }
          //划横线
          context.moveTo(0,a_canvas.height/2);
          context.lineTo(a_canvas.width,a_canvas.height/2);
             
          //画竖线
          context.moveTo(0,0);
          context.lineTo(0,a_canvas.height);
         
          context.lineWidth = 1;
          context.strokeStyle = "#c0c0c0";
          context.stroke();
 
          var max_v =0;
          for(var i = 0; i<data_y.length; i++){
              var d=0;
              if(data_y[i]<0){d=d-data_y[i];}else{d=data_y[i];};
			  if (d > max_v) { max_v =d};
          }
          max_v = max_v * 1.1;

		  // x轴--将数据换算为坐标 
          var points = [];
          for( var i=0; i < data_x.length; i++){
            var v = data_x[i];
            var px = cell_width *　(i + 1);
            var py = cell_height*(grid_cols - 1);
            points.push({"x":px,"y":py});
          } 
		  // x轴--绘制折线
          context.beginPath();
          context.moveTo(points[0].x, points[0].y);
          for(var i= 1; i< points.length; i++){
            context.lineTo(points[i].x,points[i].y);
          }
          context.lineWidth = 2;
          context.strokeStyle = "#000000";
          context.stroke();
		  //x轴--绘制坐标图形
          for(var i in points){
            var p = points[i];
            context.beginPath();
            context.arc(p.x,p.y,4,0,2*Math.PI);
            //空心圆
            context.strokeStyle = "#000";
            context.stroke();
            context.fillStyle="white";
            context.fill();
          }
		   //x轴--添加文字
          for(var i in points)
          {  var p = points[i];
            context.beginPath();
            context.fillStyle="black";
            context.fillText(data_x[i], p.x + 1, p.y - 15);
               
          }
		  
		  // y轴--将数据换算为坐标 
          var points = [];
          for( var i = data_y.length; i > 0; i--){
            var v = data_y[i];
            var px = cell_width;
            var py = cell_height* (i);
            points.push({"x":px,"y":py});
          } 
		  
		  // y轴--绘制折线
          context.beginPath();
          context.moveTo(points[0].x, points[0].y);
          for(var i= 1; i< points.length; i++){
            context.lineTo(points[i].x,points[i].y);
          }
          context.lineWidth = 2;
          context.strokeStyle = "#000000";
          context.stroke();
		  //y轴--绘制坐标图形
          for(var i in points){
            var p = points[i];
            context.beginPath();
            context.arc(p.x,p.y,4,0,2*Math.PI);
            //空心圆
            context.strokeStyle = "#000";
            context.stroke();
            context.fillStyle="white";
            context.fill();
          }
		   //y轴--添加文字
          for(var i in points)
          {  var p = points[i];
            context.beginPath();
            context.fillStyle="black";
            context.fillText(data_x[i], p.x + 1, p.y - 15);
               
          }
		  
		  for (var j=0; j < data_list.length; j++){
			  // 将数据换算为坐标
			  data = data_list[j]
			  var points = [];
			  for( var i=0; i < data.length; i++){
				var v= data[i];
				var px = cell_width *　(i +1);
				var py = a_canvas.height/2 - a_canvas.height*(v / max_v)/2;
				points.push({"x":px,"y":py});
			  }
			  
			  // 绘制折线
			  context.beginPath();
			  context.moveTo(points[0].x, points[0].y);
			  for(var i= 1; i< points.length; i++){
				context.lineTo(points[i].x,points[i].y);
			  }
			  context.lineWidth = 2;
			  context.strokeStyle = strokeStyle_list[j%3];
			  context.stroke();
	 
			  //绘制坐标图形
			  for(var i in points){
				var p = points[i];
				context.beginPath();
				context.arc(p.x,p.y,4,0,2*Math.PI);
				//实心圆
			   /*
				context.fillStyle = "#000";*/
				//空心圆
				context.strokeStyle = "#000";
				context.stroke();
				context.fillStyle="white";
				context.fill();
			  }
			  //添加文字
			  for(var i in points)
			  {  var p = points[i];
				context.beginPath();
				context.fillStyle="black";
				context.fillText(data[i], p.x + 1, p.y - 15);
				   
			  }
		  }
		  
		  
        },false);
      })();
 
       
</script>
</html>